Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds valuable context beyond the readOnlyHint annotation, specifying the types of filings (13D/13G with >5% stake) and specific activist examples. It is consistent with annotations and discloses the scope of the tool without contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise with two lead sentences and a brief parameter list. It front-loads the core purpose and is free of unnecessary detail, making it efficient for an agent to parse.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description adequately explains the filing type and parameters but does not describe the output format or fields returned (e.g., ticker, filer, date, percentage). Given the lack of an output schema, this is a gap that could be filled for an agent to correctly handle the result.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has no parameter descriptions (0% coverage), but the tool description compensates by explaining each parameter: target_ticker (ticker of target company), filer (activist name, post-filtered), days_back (lookback in days, default 90). This adds significant meaning beyond the schema's type and default fields.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it retrieves SEC Schedule 13D/13G activist beneficial-ownership filings, with the specific threshold of >5% stake. It names notable activists and distinguishes itself from other regulatory filing tools, such as Form 13F or Form 4, which serve different purposes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains what the tool does but does not provide explicit guidance on when to use this tool versus alternatives like get_form_13f_holdings or get_form_4_insider_trades. The context of tracking activist moves is implied, but no when-not or alternative recommendations are given.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.